Piano-forte straining-pin



(No Model.) H. B. NIOKERSON.

PIANO FORTE STRAININ-G PIN.

No. 441,438. Patented'Nov. 25, 1890.

@(QUZW 7 UNITED STATES PATENT OFFICE.

IIIRAM B. NICKERSON, OF NEW BEDFORD, MASSACHUSETTS.

PIANO-FORTE STRAlNlNG-PIN.

SPECIFICATION forming part of Letters Patent No. 441,438, dated November25, 1890.

Application filed February 26, 1889. Serial No. 301,292. (No model.)

To all whom it may concern.-

Be it known that I, HIRAM B. NICKERSON, a citizen of the United States,residing at New Bedford, in the county of Bristol and State ofMassachusetts, have invented a new and useful Improvement inPiano-Fortes, of which the following is a specification.

My invention relates to the string-plate of a piano-forteandthedeviceforgivingthe proper tension to the strings which are stretched thereon; andit consists in the peculiar construction of that part of thestring-plate in which the devices for straining the strings are located,and in the peculiar construction of the straining devices, by means ofwhich the strings are brought to the proper degree of tension, and alsoin the peculiar construction of the string-plate. I

In the accompanying drawings, Figure 1 represents a view in perspectiveof a section of a string-plate of a piano-forte, showing my improvedconstruction. Fig. 2 represents a plan view of a section of a device forpreventing the string end of the straining devices from turning whiletension is being given to the strings. Fig. 3 represents a view incrosssection of my improved straining device and the straining-abutmentin which it is located. Fig. 4 represents a view of my improvedstraining device as it appears when removed from the straining-abutmentand showing the manner of attaching the string to the same. Figs. 5, 6,7, and 8 are views of a different construction of the string end of myimproved straining device. Fig. 9 is a view in vertical cross-section ofmy improved string-plate, showing the strings passing through the plate.

In Fig. 1, arepresents a section of the stringplate of a piano-forte,the upper portion 1) of which is deflected to the rear, and'then broughtforward to practically form the arc of a circle, as Z, whose center isthe bridge 25. f represents the strings of the piano-forte. 6 representsa block, preferably of metal, having apertures g, provided with grooves72, which loosely inclose the string ends of the straining devices. Thestrings of the piano are attached to the ends of the straining devicesby passing the end through the perforation j and then coiling it aboutitself, as at s in Figs. 3, at, and 5. The wire which projects beyondthe circumference of the straining device fits in the groove h, and thusthe device is prevented fro m turning when tension is being given to thestring.

In Fig. 3, m is a rod having head 0, chiselpoint p, andlaterally-perforated at j. n is a tube having eXteriorly-squared top andinterior shoulder 10, and screw-threaded on the outside to correspondwith screw-threadin the strainingabutment l. The rod an is 1nserted inthe tube n and the string f attached,

as shown in Fig. 4., and the tube n is then screwed into thestraining-abutmentl from the under side, and then by a key or wrench isrevolved to the left until the string has the proper tension.

In Figs. 5, 6, 7, and 8 is illustrated a diiferent construction of thestring end of the straining device. Fig. 5 shows the string attached tothe end of the straining device in the proper manner, while Figs. 6 and7 show the manner in which the grooves in which the loop of the stringlies are out, while Fig. 8 shows the direction and depth of the grooveson the end of the bar. The groove i is cut diagonally across the end ofthe bar and of such a depth that the pull of the string when it isattached, as in Fig. 5, will be from the center. The groove 10 is cutparallel with the length of the rod and directly in line with theperforation j, as is fully shown in Fig. 7.

In Fig. 9 the top of the string-plate is deflected to the front and thencarried to the rear to form the arc of a circle whose center is theapertures q, through which the strings f pass to the front of the plateand over the bridge 75.

WVhatI claim, and desire to secure byLetters Patent, is-

1. In a piano-forte, the combination of a when the string is attachedits thickness will lie outside of the circumference of said rod, with abar of metal or other suitable material adapted to lie against thedeflected portion of the string-plate and apertured to loosely 1),lateral aperturej, and head 0, and the tube n, exteriorly screw-threadedand provided with squared top 1' and having interior shoulder w, onwhich the head of the rod m rests, all as shown and described.

HIRAM B. NICKERSON.

Witnesses:

J. L. GILLINGHAM, HENRY W. MASON.

